The Bristol Shubunkin standard is as follows:
Depth of body to be between approximately 35% of body length.
Caudal fin to be single and well spread with rounded lobes.
Dorsal and anal fins to be single, pectoral and pelvic fins to be paired and their extremities slightly rounded.
At least 25% of the body to be blue.
Minimum body length to be 7.5 cm (3 inches).
The fish should be bright and alert. The body should be long and slender with a smooth outline. The caudal fin should be well spread without drooping or overlapping.
Only calico fish to be shown. Fish should have a blue background with patches of violet, red, orange, yellow, brown and white, spotted with black. Quality fish should have a high intensity of colour evenly distributed over the body, with colour, especially black, extending into the fins.